Publication DE 197 40 985 C2 discloses punched knitting tools, in particular latch needles, that are adapted to be moved back and forth in longitudinal direction in guiding grooves of corresponding needle beds. These knitting tools comprise a shaft configured as a meander-shaped strip that defines a first height and extends away from the foot. The thickness of this shaft is reduced at some points. Extending from the shaft, there is a straight shaft extension that has, on its end remote from the shaft, a stitch-forming part that is configured, for example, as a hook and an immovably supported latch. In doing so, the stitch-forming part is that part of the knitting tool that is needed for the formation of stitches. The straight shaft extension has a second height that is lower than the first height of the shaft. The shaft extension has a uniform height. It is only the transition between the shaft and the shaft extension that is still configured with reduced thickness.
Such knitting tools have proven themselves to be excellent in practical applications because they allow faster knitting speeds.
There exist numerous additional suggestions for providing knitting tools with locations of reduced thickness. For example, German Patent 680 319 discloses a knitting tool with a laterally flexible shaft that is adjoined by a non-thickness-reduced shaft extension. During the knitting operation, the shaft is driven out of its guiding groove so that the thickness-reduced region of the shaft may act as a laterally flexible leaf spring. For a stitch transfer, the laterally flexible needle can be resiliently bent by a control member in order to come into contact with another needle.
As opposed to this, German Patent 20 63 724 discloses a needle, in which case the shaft displays reduced thickness in the region of the needle foot. This is to allow an elastic deformation of the shaft in order avoid a jamming of the shaft when it impacts the needle foot on a tappet part.
Publication DE 36 12 316 A1 discloses another embodiment of a needle with partially reduced thickness. In that case, the flanks of the shaft of the needle are provided with flat grooves extending in longitudinal direction. The shaft may be configured as a meander-shaped strip. A shaft extension extends from said shaft, said extension transitioning into a stitch-forming structure at its end. The shaft extension displays non-reduced thickness of the shaft.
Furthermore, publication DE 199 39 929 A1 shows a needle having a shaft that is provided, along its entire length, with dimples or extensions that form a concave or convex pattern. A knitting tool having a convoluted shaft is also known from this publication.
Considering all the aforementioned needles, the knitting speed of the knitting machine also increases the power necessary for driving the needles, as well as increases the machine temperature.